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The objective of this study is to investigate potential diversified transportation energy source solutions and their effective use up to 2030 in order to establish sustainable energy use in road transportation. Five Association of Southeast Asian Nations (ASEAN) countries (Thailand, Indonesia, Malaysia, Philippines, and Vietnam) are examined by considering their economy, energy status, and automotive market scale. In this study, existing energy policies, fuel supply, demand status, petroleum and alternative fuel products, such as natural gas and biofuels, and oil refining/biofuels production capacity are investigated as components of energy mixing. If there are gaps between oil reduction targets and Business as Usual (BAU) consumption, or the required amount of biofuel use to achieve introduction target and possible supply, measures such as improved new vehicle fuel economy, adjustment of biofuel utilization, and natural gas utilization are considered to minimize gaps or to meet policy targets. An appropriate and cost-effective combination of measures is proposed as an alternative case for each country’s needs. Results show that biofuel utilization is one of the measures that is crucial in meeting policy targets. Even in the alternative case, however, estimated demand volume of biofuel exceeds domestic supply volume in some countries, while estimated demand volume of biofuel is lower than domestic supply volume in other countries. In order to solve these gaps and cultivate biofuel security within the ASEAN region, a concept of multi-national cooperation of biofuel is proposed. Creating policies to diminish barriers that prevent the trade of biofuels between neighboring countries is the key to success.

Surface potential switching on gold(111) surfaces is induced by complexation/decomplexation reactions of a bipyridine (BP) derivative and palladium(II) chloride, as observed by Kelvin probe force microscopy (KFM). On the basis of the theoretical predictions, a 4-(5-phenylethynyl-2,2'-bipyridine-5'-yl-ethynyl)benzenethiol (PhBP) derivative was synthesized and used as an active monolayer to catch transition metal ions. By using the microcontact printing (CP) technique, micron-size patterned PhBP monolayers, which act as effective hosts to coordinate palladium(II) chloride, were prepared on gold(111) surfaces. The KFM signal decreases by complexation of the Pd(II) chloride in PhBP monolayers and is recovered by removal of Pd ions using an ethylenediamine solution, as confirmed by X-ray photoelectron spectroscopy. This process is reversible, indicating that the surface potential switching is realized by complexation/decomplexation of Pd(II). A CP PhBP monolayer, when it detects the target palladium ion, shows sensitivity for the picomolar level detection judged from surface potential changes in KFM measurements. The dipole moment estimated by the surface potentials is much smaller than the calculated value, indicating that mechanisms for the reduction of the surface dipole moment exist in real monolayers prepared by the CP method.

Microcontact printing (μCP) is the first soft-lithographic technique developed by Kumar and Whitesides in 1993. At first, it was mainly used to pattern thiol self-assembled monolayers on metal surfaces, but later on, has been applied to various materials, including biological molecules. Because of its wide application, the μCP is considered to be not only a patterning technique, but also used as a convenient soft-manufacturing method. In this article, basics and recent topics of the μCP are overviewed. Main technical developments are targeting on the biological applications and the fabrication of organic transistors. We introduce up-to-date technical achievements of the both fields. In addition, efforts to scale down the pattern resolution and unique applications utilizing the properties of the stamp material are mentioned.

We are investigating electrical properties of multiwalled carbon nanotube (CNT) probes for scanning tunneling microscopy (STM). To improve the electrical conduction and reduce the contamination at the interface to the gold base, we selected conductive CNTs and heated the base and CNT during the CNT attaching process. Before STM measurements, the probes were cleaned by annealing in vacuum for 4–8 h. With these treatments, we found a small number of tips exhibiting linear metallic current–voltage (I–V) curves on Au(111), while all the CNT tips attached on gold (not heated) exhibited nonlinear I–V curves. We discuss the possibility that the metallic behavior of the CNT probes may be caused by the diffused gold atoms along the CNT surfaces by the long heat treatment.

Oligo(para-phenylene-vinylene)-methanethiol of trimer and dimer have been synthesized to prepare monolayers onto Au(111). The trimer diluted in dichloromethane glows with a brilliant blue fluorescence when excited with UV light (365 nm). The absorption and emission spectra of the dimer diluted in CH 2 Cl 2 show a blue shift. The molecular level morphologies of the monolayers prepared on gold surfaces were probed by scanning tunneling microscopy or atomic force microscopy (AFM). The dimer is entire trans isomer, which formed highly ordered self-assembled monolayers (SAMs) on Au. The trimer is a mixture of cis–trans isomers, and did not form ordered monolayers on Au. However, the trimer molecules could be embedded in dodecanethiol SAM, and showed higher conductance than oligo(para-phenylene) molecules characterized using a conductive AFM.

We demonstrate a high yield production scheme to fabricate sub-10 nm co-planar metal-insulator-metal junctions without using electron beam lithography. The fabricating procedure contains two photolithographys followed by shadow evaporation. Ultrasmall gaps were formed in the crossing region of the two metal layers during the evaporation of the second layer. The sizes of the gaps were estimated using scanning electron microscopy images. Poly (3-hexylthiophene-2,5-diyl) layers were deposited on the junctions using a special ink-jet technique. The results of the conductivity measurement of the molecular layer indicate that these junctions can be used in the study of molecular sensors.

Carbon nanotubes (CNTs) have attracted much attention for their unique properties, although their formation mechanism is not well understood. The authors have been studying a technique to form CNTs by an electron beam that is carried out in a transmission electron microscope (TEM) and is compatible with in situ and real-time observation of the growth. The observation, where a precursor (polyyne-containing carbon) is heated and irradiated by an electron beam, shows that the growth occurs in two steps: rapid formation of rodlike carbon (first step) and slow graphitization of its wall (second step). The hollow inside the CNT is not formed in the first step and develops during the second. The formation mechanism is discussed in relation to in situ observations.

The electrical conduction of self-assembled monolayers (SAMs) made from conjugated molecules was measured using conductive atomic force microscopy (AFM), with a focus on the molecular structural ef...

The mechanism of the carbon nanotube (CNT) formation and its graphitization has not been well understood and is still under controversy. The authors have been studying a new process to form CNTs, where polyyne-containing carbons are heated and irradiated by an electron beam in a transmission electron microscope (TEM). The technique is compatible to an in-situ observation and was applied to a high-resolution TEM (HRTEM) to elucidate the graphitization mechanism. The observation shows that micro-graphenes exist from the beginning of the formation process and develop to form highly ordered graphene layers through fusion and rearrangement of the premature layers, accompanied by evaporation of micro-graphenes. The CNT formation mechanism focusing on its graphitization is presented and discussed.

A new way to form carbon nanotubes (CNTs), carbon nanocapsules (CNCs), and carbon nanoparticles (CNPs), where polyyne-containing carbons are heated and irradiated by an electron beam in a transmission electron microscope (TEM), has been developed. The technique was applied to carry out an in-situ observation of those formation processes. Though the CNPs have been reported to be formed accompanied by the CNTs, the CNPs and the CNCs were found to be formed independently from the CNTs. The CNTs are preferentially inside of the polyyne-containing carbon films, while the CNPs/CNCs are outside of the films. The difference of the inside and the outside are discussed to lead to understanding of the CNC and CNP formation process. From the in-situ observation, the existence of metal particles, the high surface energy, the high wettability, and the high viscosity of the polyyne-containing carbons are assumed to be relevant to the preferential formation of CNCs/CNPs to CNTs.

We have investigated an insertion process of conjugated molecules, 4-biphenylmethanethiol (BP) and [1,1′:4′,1″-terphenyl]-4-methanethiol (TP) into preassembled n-alkanethiol self-assembled monolayers on Au(111) using scanning tunneling microscopy (STM). Ex situ STM observation revealed that the insertion process is dependent on an organic solvent in which the conjugated molecules dissolve. The insertion of conjugated molecules with three phenyl rings (TP) was faster than that with two phenyl rings (BP). By analyzing the STM images, the lower limits of resistances for single BP and TP molecules were obtained as 22±5 and 36±5 GΩ, respectively.

We have studied the phase-separation of self-assembled monolayers (SAMs) of dialkyl disulfides on Au surface. Initially, the heat-induced phase-separation of SAMs consisting of unsymmetric disulfide molecules (CF 3 (CF 2 ) 5 (CH 2 ) 2 SS(CH 2 ) 7 CH 3 ) of hydrocarbon and fluorocarbon chains was investigated. We proved that the dimer structure cleaved on the Au surface. Subsequently, we formed one-dimensional nanostructures utilizing an anisotropic phase-separation of SAMs consisting of a mixture of the above unsymmetric disulfide and a symmetric disulfide of hydrocarbon (CH 3 (CH 2 ) 7 SS(CH 2 ) 7 CH 3 ). The wire-like structure with a width of 5 nm and a length ≈100 nm was observed by scanning tunneling microscopy.

An efficient method was developed to stretch DNA molecules on an atomically flat surface for AFM imaging. This method involves anchoring DNA molecules from their 5' ends to amino silanized mica surfaces. N-Succinimidyl6-[3'-(2-pyridyldithio) propionamido]hexanoate (LC-SPDP), a heterobifunctional cross-linker with a flexible spacer arm was used for this purpose. The immobilization process was carried out by introducing a thiol group to the 5' end of DNA by PCR. Thiolated molecules were then reacted with the cross linker to conjugate with its 2-pyridyl disulphide group via sulfhydryl exchange. The resulting complex was deposited on amino silanized mica where NHS -ester moiety of the cross linker reacted with the primary amino group on the surface. Samples were washed by a current of water and dried by an air jet in one direction parallel to the surface. DNA molecules were shown to be fully stretched in one direction on imaging them by AFM.

The scanning tunneling microscope (STM) was invented less than five years ago by G. Binnig and H. Rohrer. In 1986 they were honored with the Nobel prize in physics, together with E. Ruska who invented the transmission electron microscope in 1933. The principles of the STM and the construction of the instruments are described by dividing them into several key technologies: (i) vibration isolation; (ii) course and fine positionings and scannings; (iii) thermal drift, hysteresis, and creep of piezoactuaters; (iv) metal probes; and (v) electronic control circuits. Surface structures recently observed by the STM on metals, semiconductors, etc. are reviewed. The future development of the STM is mentioned very briefly.

A helium refrigerator system equipped with low-temperature centrifugal compressors is proposed. This refrigerator, named L-system refrigerator, is operated almost below the temperature of liquid nitrogen. It has higher reliability and capability of long time continuous operation free from the contamination of helium with oil and from wear of moving part. It also has an advantage that the control of refrigeration power is easily achieved by adjusting the speed of compressors. The direct input power to the L-system refrigerator is lower, but it thermal efficiency is almost same as the conventional one, when the energy necessary to make liquid nitrogen is taken into account.A L-system refrigerator with refrigeration power of 1, 500W at 20K level is designed based on the experimental results of the low-temperature centrifugal compressor developed at Electrotechnical Laboratory. Its refrigeration power at 20K varies from 930W to 2, 000W almost lineary by changing the rotational speed of the compressors from 500rps to 720rps. The direct input power is 17kW to 35kW, but it consumes 310kg to 630kg of liquid nitrogen par hour.Large capacity helium refrigerators with high reliability and efficiency will be materialized when L-system refrigerators are built near the region where a large bulk of coolant is easily obtained, such as a LNG repository.

Centrifugal helium compressors were developed to improve efficiency and reliability of helium refrigerators. These comprssors are operated almost below the temperature of liquid nitrogen. The rotor of the compressor is supported by helium lubricated gas bearings. A controlled attractive magnetic bearing is adoptted as auxiliary.Two compressors were manufactured. The 1st. trial one was made simply for experiment to study the possibility of low-temperature helium compressors. The 2nd. trial one was made taking practical use into consideration in respect to flow rate and compression ratio.This paper describes mainly the 2nd. trial compressor. Its typical specifications are as follows: type: two-stages centrifugal compressor with intercooler, flow rate: 75g/s, total compression ratio excluding the pressure loss in intercooler: 1.69, inlet helium temperature: 80K, rotational speed: 700rps (42, 000rpm), motor output: 10.2kW, type of bearings: helium lubricated internal tilting pad radial bearings and a spiral grooved thrust bearing with a controlled attractive magnetic bearing.The compressor was installed in a vacuum chamber for cold test, and the performance was examined in a closed loop. Items to be measured are rotational speed, electric input power, flow rate, pressure and temperature of helium gas at each inlet and outlet ports, vibration of the rotor and the current of the magnetic bearing. The results showed that the compressor excelled the expected values in performance. The following is the principal performance at the rated rotational speed, total compression ratio at the flow rate of 74.8g/s: 1.76, adiavatic efficiency: 1st. stage; 71%, 2nd. stage; 73%, total efficiency: 62%. The rotor supported by the bearing above mentioned operated stably up to 44, 000rpm. The controlled attractive magnetic bearing gave an adequate clearance to the thrust gas bearing in start and stop condition, so that the rotor was able to start many times without any damage to the gas bearings. The compressor has operated for a long time.

Conventional roll forming processes for electric-resistance-welded (ERW) pipes are outlined with respect to roll contours, stand arrangements and deformation strains during forming. The developmental history and features of a new process (VRF process) for forming ERW pipes by constraining the strip edges with undriven vertical rolls are described. The equipment characteristics, fundamental forming characteristics and forming load characteristics of the new process are compared with those of the conventional ER W pipe roll forming processes. Neutral line constant as pass line and uniform displacement distribution as forming distribution are found to be the optimum combination for the VRF process. The results of the present study show that this process can reduce edge stretch and forming energy, and is expected to save roll, equipment and energy costs when put to commercial use. The dimensional tolerances of pipe products manufactured in preliminary commercial production experiments are also described.